On November 3, 2022, Amir Moftakhar, Chief Financial Officer of ESS Tech, Inc. tendered his resignation as Chief Financial Officer to be effective as of November 4, 2022. Mr. Moftakhar will continue with the Company as a non-executive employee to facilitate the transition of chief financial officer responsibilities through December 31, 2022. Thereafter, Mr. Moftakhar will continue with the Company in an advisory capacity from January 1, 2023 to January 24, 2023 unless such date is extended by mutual agreement prior to such date.

On November 3, 2022, the Company announced the appointment of Anthony Rabb as the Company's principal financial officer and principal accounting officer. Mr. Rabb, age 54, has over 30 years' experience in various finance functions. Mr. Rabb previously served as the Chief Financial Officer and Senior Vice President of Total Safety, Inc. from August 2020 until June 2022, with responsibility for Total Safety, Inc.'s finance, accounting, treasury, tax, risk management and information technology matters.

Prior to that, Mr. Rabb served as Chief Financial Officer and Executive Vice President of Mirion Technologies, Inc. from October 2015 until February 2020. Mr. Rabb has also been Chief Financial Officer of Vigor Industrial, Brand Energy, GE Measurement and Sensing Technologies, and Vice President of Mergers and Acquisitions of GE Capital. Mr. Rabb holds a Bachelor of Arts degree in Economics from the University of Colorado, Boulder.